Newsletter 2014-4 October 2014 www.variablestarssouth.org Tom Richards resigns as director - will concentrate on research Contents From the director — Tom Richards ............................................................................................................... 2 Editorial ................................................................................................................................................................................3 O-B5 Stars in Centaurus: re-evaluation of published data - Mati Morel .............................5 Simplest CCD photometry - Tom Richards ...............................................................................................7 CCD targets in the EB/EW Project - Tom Richards ............................................................................9 Southern semi-regulars – a progress report – Aline Homes ....................................................10 SY Fornacis - a high galactic latitude binary star – Stan Walker ...........................................14 The long period variable - dual maxima Mira scene – Stan Walke .........................................16 Bright Cepheids in the 2015 season – Stan Walker ........................................................................17 Transforming magnitudes in the I passband – David Moriarty .................................................18 The EB & EW binaries project update – Mark Blackford ............................................................20 The Orion Project - for serious amateur astronomy – Carl Knight ........................................22 Publication Watch ......................................................................................................................................................30 About ...................................................................................................................................................................................31 VSS Newsletter 2014-4 1 From the Director - Tom Richards [email protected] Alan Baldwin to lead Beginners Visual Project Worldwide experience indicates that to attract amateur astronomers to variable star work, and to keep them there, nothing is as valuable as visual photometry – simply done with basic equipment. From the beginning of VSS six years ago, Alan Plummer, one of Australasia’s best known visual observers and researchers, volunteered to set up and run a beginners visual observing project for VSS. Of late, Alan has indicated to me he’d like to pass on this role to another, and concentrate on his important R/Eta Car project, as well as family and his musical career. VSS has been very lucky in finding an excellent replacement, New Zealand’s Alan Baldwin. I first knew Alan B when we were both schoolkids, enthusiastically using Wellington College Obser- vatory. Since that time, Alan has maintained his contacts with RASNZ and his variable star work, and will be well remembered from his presence and work at VSSS3 in Whakatane earlier this year. Alan has prepared some material to send to enquirers and will act as a first point of contact and coordinator of the Beginners Project. Thank you very much for taking on this role, Alan. I’m sure that established visual variable star observers will give you every support; and I’d like to invite leaders of astronomy club vari- able star groups and others to contact Alan to see how you can help each other and inspire newcomers. You can email him at [email protected]. Finally I’d like to thank our other Alan very warmly for the work you have done in this project over the years. I know that you’ll be continuing your education and outreach passion locally, as well as continuing your excellent column in Australian Sky and Telescope. And there’s always the big R/Eta Car project. Time to replace this director I have tendered my resignation as Director to the Council of RASNZ, effective December 31st. Over the nearly six years since I became director of the moribund variable star section of RASNZ and renamed it, it has grown into a thriving and successful research organisation. It now has thirteen projects led by various very able astronomers. Its membership, though that is now an informal concept, hovers around 50-60 and its finances are strong. It has run three symposia with 30 or more attendees, presented papers at every RASNZ and NACAA conference, and has an accelerating stream of refereed publications in recognised astronomical journals. This is thanks to the dedicated work of many VSS members, who have taken leadership roles as well as observing and research. With VSS in such a strong and healthy state, I have decided this is an opportune time for me to hand over to another leader (or leadership team) with another vision. Because of the diversified non-centralized nature of VSS it is to a large extent functioning autonomously and it will not be hard for a new leader to take up the position. I am very ably assisted by three office-bearers: Bob Evans for financial matters, Phil Evans editing the newsletter, and David O’Driscoll as webmaster. I am sure these three will provide con- tinuing support to a new director. In addition Stan Walker has been a close and invaluable adviser with far more knowledge than I have, and I’m confident he will be willing to assist whoever replaces me. We are not an incorporated body and do not have a formal structure, so the task of deciding on a re- placement, or replacement team, is also informal. I have asked the office-bearers and project leaders to discuss the succession and formulate a decision on it – before my resignation date. It would be very good if anyone associated with VSS work expressed their views on the succession on our email forum. We are certainly not bound by the present structure of a single “director” responsible to RASNZ; we can take VSS where we want and organise it as we think best. 2 VSS Newsletter 2014-4 Although I think VSS is functioning very successfully in its present form, I do think there are important new directions we can and should develop. Here are three: you may think of more (and should discuss them on our forum). • Internationalise beyond Australasia, in particular to South America and southern Africa. • Establish strong and enduring working relationships with appropriate professional astronomers and institutions. • Develop new types of research activities beyond the “project”. So please give the situation some thought and make your views known, so they can be considered in a succession plan. Finally I’d like to thank everyone who has contributed to VSS over the last six years, particularly the office-bearers and project leaders. You have grown VSS from essentially nothing to what it is today, and have made my job exciting and joyful. Now let’s move on to better things. Editorial [email protected] In this issue of the newsletter Tom Richards formally notifies all members of his resignation as director of Variable Stars South. Behind the scenes there has been some discussion among team leaders and office bearers about a possible successor but with no conclusions. It is time to bring all members up to date with that discussion and to encour- age further contributions. The following comments have all come from mem- bers and the director and much of it is lifted verbatim from the emails. One thing all are agreed on is that we owe a tremendous debt to Tom for setting up and running the group for six years and that we wish him well in his retirement (from the position but not from astronomy). Tom has laid out the jobs that he now does routinely and they are: • Encouraging new projects, helping leaders set them up, getting the right material onto the website and elsewhere, monitoring progress and advising • Welcoming new “members”, encouraging members to get involved in appropriate research, answering email questions, and the like. • January report to RASNZ (Bob provides the balance sheet) • Checking Newsletter content before publication, writing From Director and other VSS-level material • Close liaison over the website - content, organisation, presentation, updating, writing for it • Coordinating between different areas as the need arises • Maintenance of the eclipsing binary database • Less specifically, a lot of miscellaneous work, arising because everybody else has very specific roles so anything outside those roles must fall to the director. And he sets out possible new directions for us above. There seems to be a consensus forming among the contributors to the discussion that some kind of team is needed now to run VSS. It has been suggested that we can manage without a specific leader as all our projects are running smoothly, but many feel that we should have a nominal leader, not least for political reasons. VSS Newsletter 2014-4 3 It is true that we have strong project leaders and finance, web and newsletter are all taken care of and we could simply carry on leaderless, but from where would the drive and impetus come for improvement and expansion? In the past the Photometric Section of the RASNZ had two, and for a time, three directors, good work- ing relationships with the three main NZ groups and many overseas professionals. In contrast, VSS finds itself in a changed environment where liaisons seem based around such groups as CBA with CVs, Mi- croFun and others with planetary detection and where the AAVSO is trying to establish a monopoly with variable star observing. At present we are not an incorporated body and have no formal means of